As energy becomes more expensive, work has accelerated on the development of systems and methods to improve the efficiency of utilization of energy. In this connection, various attempts have been made to design systems to control energy utilization at geographically distinct facilities from a single control facility. A typical implementation of this sort, among other possible capabilities, includes the centralized control of the energizing of energy-utilizing devices at the various facilities.
Typically, such implementations, e.g., call for a station at an energy-utilizing facility to receive only one of a number of frequencies, so as to be independently addressable from the central facility, such as in Stevenson U.S. Pat. No. 4,023,043. Perhaps even more commonly, the independent addressing capability is provided by digitally coding an address to which only one or a group of stations (or controls) is responsive, as in Pai U.S. Pat. No. 4,130,874, Miller et al U.S. Pat. No. 4,167,786, Wu U.S. Pat. No. 4,163,218 and Bogacki U.S. Pat. No. 4,161,720.
The digital coding, as indicated among these patents, may well be grounded in frequency (the presence of a given frequency being high and its absence being low, or one frequency being high and another frequency being low), with, for example, one or more stations only receptive to a code of codes grounded in a certain frequency or frequencies. This is well illustrated in Bogacki, supra.
The dependence of addressing upon the frequency of the output from the central facility or upon an encoded address generated and transmitted by the central facility typically results in complicated and expensive components and designs at both the transmitting end and at the receiving end.
This is well illustrated by all of the above patents, apart from Stevenson which is presented more generally than others.
Such expense, along with, commonly, tailored design requirements for each remote station or for each of several groups, substantially decreases the economic viability of the general concept.
The present invention addresses the concept of the remote control of energy utilization at remote facilities in a way which provides not only simplicity of design, but simplicity of operation. Such is accomplished through apparatus which transmits a plurality of channels of information which are all received and operated on at each of the remote facilities. Apparatus which transmits time-multiplexed channels and, in each terminal, which responds to, operates on and stores the information in such channels, provides for ready channel selection, to control load networks at the facility associated with the terminal.